Compasses.



PATENTED-JUNE 4, 1907.

e. SOHOENNER. GOMPASSES.

APPLICATION FILED NOV. 28, 190B- IIIIIIIII 3 Es wlTmEgfQv w. RM

GEORG SCHOENNER, OF NUREMBERG, GERMANY.

COMPASSES.

Specification of Letters Patent.

Patented. June 4, 1907.

Application filed November 28,1906- selial N0 34:5,54z2- To aZZ whom itmay concern:

Be it known that- I, GEORG SoHoENNER, manufacturer, a subject of theGerman Emperor, residing at Nuremberg, Bavaria, Germany, have inventednew and useful Improvements in Compasses, of which the following is aspecification.

This'invention relates to an improvement in those means of securingattachments in compasses in which the pin of the attachment is insertedin the slotted end of the compass arm, which end is formed as a springsheath or socket. By the modification of this known means of securingthe attachment Which forms the object of the present invention it isintended to produce near the free ends. of the lugs of the compass arm,a clamping device, which may be regulated, supplementary to the springpressure of the said lugs, and thereby to render the clamping connectionmore reliable. This object is attained by the ends of a strip springbearing against the lug of one of the compass arms, the middle of whichspring is engaged by a tightening screw passing through both lugs of thearm, and in accordance with the screw being tightened up, exerts agreater or lesser pressure against the root as well as against the freeend of one lug of the arm.

An attachment securing device of this kind is shown in Figs. 16 of theaccompanying drawings.

The sheath or socket b, forming the end of the compass arm, has alongitudinal perforation e receiving the pin 0 of the attachment d andis divided into two spring lugs 7L and 'i by an elongated slot g merginginto a cross perforation f. These lugs are traversed with some play by atightening screw 7c, the head Z of which, bears against the lug h of thearm, and its other end carries a thread m. With this thread m the screwengages in the middle part of an outwardly curved strip spring 0inserted in the recess a on the lug i of the arm and thereby the springis drawn against the lug of the arm in such a way that its ends bearagainst the root and the free end respectively of this lug t. screwbeing turned, it is possible to regulate the pressure exerted by thestrip spring on the free end of the lug & of the arm, and consequentlyto obtain a reliable but easily released clamping connection.

By the same screw the direction of the attachment may also be securedand a special v directing wedge dispensed with. For this object theattachment pin 0 is merely made long enough to project upward into thesocket above the screw 7c, which then in turn is inserted through alongitudinal slot p in this pin 0.

I declare that what I claim is Means for securing an attachment in compasses comprising a leg having two lugs at its end forming a receivingsocket for the attachment, one of said lugs having a recess on its outerface, a curved spring in said recess and a tightening screw passingthrough both lugs and engaging the middle part of the spring.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

GEORG SCHOENNER.

Witnesses:

LEONHARD KOERBER, HERMANN DOEHLEMANN.

Now by means'of the

